Like an electrophotographic toner containing a color former compound proposed in JP-B-3457538, etc., a toner having an achromatism is known. Such a toner can be produced through a so-called kneading and pulverization process. In the process, a toner is obtained by melt-kneading a color former compound, a color developer agent, a de-coloring agent, a binder resin, etc., thereby dispersing the color former compound, the color developer agent, and the de-coloring agent in the binder resin, and finely pulverizing the resulting solid to about several μm. This toner is in the form of a powder and is in a colored state (color-developed state), and the colored state is maintained even after the toner is transferred onto paper and fixed thereon by heating. For the erasure, the paper is fed to an erasing device and heated therein, thereby erasing the image. However, in this method, a color former compound, a color developer agent and a de-coloring agent are melt-kneaded at the same time, and therefore, this method has a disadvantage that if a de-coloring agent which is basic and has a strong de-coloring (or achromatizing) action is used, the developed color density is decreased or the color is lost. Meanwhile, if a de-coloring agent having a weak color achromatizing action is used for increasing the developed color density, the erasing speed becomes low, and therefore, it is necessary to perform heating for along time for erasing.